Board Thread:Pokémon Help/@comment-32771707-20170804181357/@comment-30804097-20170805184823

Mamoswine should have Earthquake, Ice Shard, Stealth Rock, and Icicle Crash or Icicle Spear (both Egg Moves you can get by breeding with Alolan Sandslash).

Its item should be Life Orb, and its ability should be Thick Fat unless you don't want to HA breed, which I guess you can go with Oblivious.

EVs should be 252 Speed and 252 Attack with 6 in HP.